1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
seraphim [82]
3 years ago
13

A merry-go-round rotates from rest with an angular acceleration of 1.45 rad/s2. How long does it take to rotate through (a) the

first 3.70 rev and (b) the next 3.70 rev?
Physics
1 answer:
elena55 [62]3 years ago
7 0

Answer:

(a) t = 5.66 s

(b) t = 8 s

Explanation:

(a)

Here we will use 2nd equation of motion for angular motion:

θ = ωi t + (1/2)∝t²

where,

θ = Angular Displacement = (3.7 rev)(2π rad/1 rev) = 23.25 rad

ωi = initial angular speed = 0 rad/s

t = time = ?

∝ = angular acceleration = 1.45 rad/s²

Therefore,

23.25 rad = (0 rad/s)(t) + (1/2)(1.45 rad/s²)t²

t² = (23.25 rad)(2)/(1.45 rad/s²)

t = √(32.06 s²)

<u>t = 5.66 s</u>

<u></u>

(b)For next 3.7 rev

θ = ωi t + (1/2)∝t²

where,

θ = Angular Displacement = (3.7 rev + 3.7 rev)(2π rad/1 rev) = 46.5 rad

ωi = initial angular speed = 0 rad/s

t = time = ?

∝ = angular acceleration = 1.45 rad/s²

Therefore,

46.5 rad = (0 rad/s)(t) + (1/2)(1.45 rad/s²)t²

t² = (46.5 rad)(2)/(1.45 rad/s²)

t = √(64.13 s²)

<u>t = 8 s</u>

You might be interested in
A Person whose weight is 5.20 x 10^2 N is being pulledup
Gnoma [55]

Answer:

Explanation:

Given

Weight of Person W=5.20\times 10^{2} N

Cave is h=35.1 m deep

Breaking stress T=569 N

Net Force on Person

F_{net}=569-520=49 N

a_{net}=\frac{F_{net}}{\frac{W}{g}}

a_{net}=\frac{49}{\frac{520}{9.8}}

a_{net}=0.923 m/s^2

The shortest time such that the person can be taken out of cave

h=ut+\frac{1}{2}at^2

where

h=distance moved

t=time

a=acceleration

35.1=0+\frac{1}{2}(0.923)(t)^2

t^2=76.05

t=\sqrt{76.05}

t=8.72\ s                    

6 0
3 years ago
A plane flies along a straight line path after taking off, and it ends up 220 km farther east and 100.0 km farther north, relati
love history [14]

Answer:

North east

Explanation:

The distance travelled by a plane from one point to another is the shortest distance between the two points. This distance travelled is usually a straight line path from point 1 to point 2.

Since the plane ends up 220 km farther east and 100.0 km farther north, the direction of flight for the plane is in the North-East direction.

Let x represent the distance travelled by the plane. Hence:

x² = 100² + 220²

x² = 58400

x = 241.66 km

3 0
2 years ago
Atoms are the smallest portions of an element that retain the original characteristics of the element. True or false
kozerog [31]

Answer:

True

Explanation:

Going even smaller than atoms would get you to subatomic particles such as quarks. From there, it is impossible to distinguish elements. So, yes, atoms are the smallest portions of an element that retains the original characteristic of the element.

4 0
3 years ago
PLEASE HELP A cup of water and a swimming pool full of water are at 24°C. The _____ of the swimming pool is higher. 1.heat conte
Dimas [21]

Answer:

4. kinetic energy

4 0
3 years ago
Kelli weighs 440 N, and she is sitting on a playground swing that hangs 0.41 m above the ground. Her mom pulls the swing back an
kifflom [539]

Answer:

Explanation:

Initial height from the ground = .41 m

Final height = 1m

Height by which Kelli was raised ( h )= .59 m

When she passes through the lowest point , she loses P E

= mgh

= 440 x .59

= 259.6 J

kinetic energy possessed by her

= 1/2 mv²

= .5 x (440/9.8) x 2²

= 89.8 J

Difference of energy is lost due to work by  air friction

work done by  friction = 89.8 - 259.6

= - 169.8 J

4 0
3 years ago
Other questions:
  •                  All the processes that form mountain ranges are known as                
    10·1 answer
  • A train travels at a speed of 30 miles/hour and traveled a distance of 240 miles. How
    14·1 answer
  • Emir is standing in a treehouse and looking down at a swingset in the yard next door. The angle of depression from Emir's eyelin
    10·2 answers
  • two object gravitationally attract with a force of 20N.if the distance between the two object centers is doubled, then what is t
    12·1 answer
  • How do elastic objects behave when different forces are applied?
    12·1 answer
  • A rifle with a longer barrel can fire bullets with a larger velocity than a rifle with a shorter barrel. a) Explain this using t
    12·1 answer
  • A more powerful engine means a plane will have a
    13·1 answer
  • Is sound only formed from vibration of particles​
    8·1 answer
  • A car is stopped for a traffic signal. When the light turns green, the car accelerates, increasing its speed from zero to 9.41 m
    12·1 answer
  • 3. What is the acceleration of a car at rest that stays at rest over 10 seconds?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!